In known apparatus for storing and heating food products, trays with integrated resistance heating element are used, that have the disadvantage of being extremely expensive. Moreover, these trays are heavy, and preclude the use of disposable trays. Other apparatus include heat barriers that separate the products to be reheated from the refrigerated products, but these heat barriers do not function individually for each tray. Instead, they function all at once in the apparatus, and for all the trays, at the same time. This has the disadvantage of requiring the heating of all the trays at the same time, and thus, not permitting the heating of one individual tray in accordance with requirements, and keeping the heated trays waiting in a refrigerated atmosphere.
These latter apparatus may be appropriate for mass distribution of meals in trays at the same time, because there would not arise the situation of keeping plates waiting to be heated in a refrigerated atmosphere, without having to remove the tray, before it is brought to an appropriate temperature and is distributed, even though the resistance heating element of the trays are individual, the heat from these is communicated to the neighboring trays.
The cold air flow being stopped at this moment, this results is a quick rise in temperature in the refrigerated atmosphere, even though the resistance elements of all the trays were not subject to electric current. French Patent FR-A-2,285,836 describes a system which includes a refrigerated housing containing supports for meal trays, equipped with heating areas for selectively reheating some plates at a given moment. However, once the meal tray has been removed, these heating areas do not become cold instantaneously, and the residual heat must be compensated with introduction of kilogram cooling addition cooling heat, which diminishes the overall efficiency of the installation.
The apparatus, according to the invention eliminates all of these disadvantages enables, the use of disposable trays made of plastic, ABS, polystyrene, cardboard or any other "ephemeral" products, and it enables each tray to be reheated individually or at together at the same time.